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1. Field of Invention
The security manhole insert cover relates to a locking manhole insert to prevent ingress or egress to a manhole from above or below the manhole to prevent access to underground utilities, tunnels and underneath buildings and metropolitan areas to eliminate security intrusions and terrorist attacks by underground access, which would otherwise go undetected if access to the underground utility passages were not secured. The manhole insert cover has a cylindrical locking insert barring access to the engaging and disengaging mechanism required to remove the manhole insert cover and an integrated lower cover to prevent access to the engaging and disengaging mechanism from below, the insert cover adapted to fit within a manhole without required modification of the manhole and without detection of the insert cover having been installed from above ground levels.
2. Description of Prior Art
The following United States patents were discovered and are disclosed within this application for utility patent. All relate to locking hole covers.
A first series of prior art patents involve simple manhole inserts without disclosed locking mechanisms. Those two patents, U.S. Pat. No. 6,393,771 to Stetson and U.S. Pat. No. 4,919,564 to Neathery, disclose manhole inserts, Stetson merely providing a cover and ring which insert into a manhole and allow the insert to be filled with a road surfacing material to blend in with its surrounding roadway, the insert including at least two holes to allow water to pass through the insert. Neatherly is a sealed insert to prevent water intrusion into the manhole, with a pressure relief and vent access through the insert cover.
A second set of patents disclose manhole covers with locking devices, but not secure locking devices. Those patents include U.S. Pat. No. 911,256 to McWane, which discloses a meter box cover with a hinged lid that has a rotating closure means in the hinged lid, U.S. Pat. No. 1,001,041 to Jones, which discloses a rotating lock arm attached to a manhole cover which requires a key insertion to turn the rotating locking arm, and U.S. Pat. No. 1,458,391 to Burton, which has a turning handle that when lifted, provides a rotating force to rotate a cam to disengage two arms for removal of the manhole cover. Two more recent US patents, including U.S. Pat. No. 5,082,392 to Marchese and U.S. Pat. No. 5,987,824 to Fuller, involve more detailed mechanisms to engage and disengage their manhole covers to a hole or manhole, with Fuller having a threaded conical component that travels upward when rotated, forcing several locking wedges outward, anchoring the manhole cover to the hole by outward force, while Marchese involves spring loaded locking arms that require a rotating force to retract the spring loaded arms for removal of the manhole cover, the rotating force provided by a shaped key inserted into a respectively shaped keyhole.
A third set of US patents involve secure lock mechanisms to which padlocks are supplied as the securing component. These US Patents include U.S. Pat. No. 5,328,291 to Wisniewski, U.S. Pat. No. 5,827,007 to Barton and U.S. Pat. No. 6,488,440 to Hill. Hill defines a manhole cover having a molly-type locking arm that is engaged and disengaged by several turns of the rotating shaft, to which includes an upper eyelet through which a chain is padlocked to prevent unauthorized turning of the shaft. Barton includes a locking bar bolted to a manhole insert by a nut through which a strand is pulled and padlocked to prevent removal of the nut from an upward extending stud. Wisniewski is a manhole insert having a rotating cam mechanism having a hasp that is padlocked to a stationary hasp to prevent disengagement of the extending locking arms. All three of these may be removed by the use of bolt cutters, which takes little time and makes little noise during use to bypass the securing.
None of the above devices prevent access from and under side and none of the above devices include a similar locking means, nor do they furnish the secure locking means as disclosed in the current invention. While they may each bear some semblance to the current invention, they do not, either singularly or in combination, disclose the features of the current invention.
More so now than at any time in the past, public awareness of domestic threats of security are presented, with focus on areas that would allow operations out of the ordinary perception. As this awareness increases, so does the potential for security breaches in areas that are not conspicuous, primarily those underground in urban or high security areas. Access to underground utilities, tunnel systems that travel beneath buildings and underground mass transit systems is often had through manholes that are either in the streets or sidewalks, these manholes existing for decades. In lieu of replacing the existing manhole systems with other costly modified access means, a security insert for manholes which offers virtual impenetrable ingress and egress is provided in the security manhole insert cover for manholes, preventing the removal of the insert cover from either the top or bottom without required alteration of the manholes.
The primary objective of the invention is to provide a security manhole seal to prevent access to underground tunnels and utilities by the application of an insert which does not require alteration of the manhole or its cover.
A secondary objective of the invention is to provide the security manhole insert cover with a completely sealed cam lock which cannot be accessed from the top or the bottom without having a key operating a cylindrical lock that denies access to the cam lock and cannot be picked , pried or cut with a mechanical tool.
A third objective of the invention is to fabricate the insert cover out of a material which can not be damaged or removed without complex intervention, i.e., plasma cutting tools and explosives, which would alert the general public to the use of such bypass means to access the manhole before such access was had. In furtherance of this objective, the entire insert cover is made of stainless steel.